<?php

/**********************************************************************
 *  Author: Justin Vincent (jv@vip.ie)
*  Web...: http://justinvincent.com
*  Name..: ezSQL
*  Desc..: ezSQL Core module - database abstraction library to make
*          it very easy to deal with databases. ezSQLcore can not be used by
*          itself (it is designed for use by database specific modules).
*
*/

/**********************************************************************
 *  ezSQL Constants
*/

define('EZSQL_VERSION','2.08');
define('OBJECT','OBJECT',true);
define('ARRAY_A','ARRAY_A',true);
define('ARRAY_N','ARRAY_N',true);

/**********************************************************************
 *  Core class containg common functions to manipulate query result
*  sets once returned
*/

class ezSQLcore
{

	var $trace            = false;  // same as $debug_all
	var $debug_all        = false;  // same as $trace
	var $debug_called     = false;
	var $vardump_called   = false;
	var $show_errors      = true;
	var $num_queries      = 0;
	var $last_query       = null;
	var $last_error       = null;
	var $col_info         = null;
	var $captured_errors  = array();
	var $cache_dir        = false;
	var $cache_queries    = false;
	var $cache_inserts    = false;
	var $use_disk_cache   = false;
	var $cache_timeout    = 24; // hours
	var $timers           = array();
	var $total_query_time = 0;
	var $db_connect_time  = 0;
	var $trace_log        = array();
	var $use_trace_log    = false;
	var $sql_log_file     = false;
	var $do_profile       = false;
	var $profile_times    = array();

	// == TJH == default now needed for echo of debug function
	var $debug_echo_is_on = true;

	/**********************************************************************
		*  Constructor
	*/

	function ezSQLcore()
	{
	}

	/**********************************************************************
		*  Print SQL/DB error - over-ridden by specific DB class
	*/

	function register_error($err_str)
	{
		// Keep track of last error
		$this->last_error = $err_str;

		// Capture all errors to an error array no matter what happens
		$this->captured_errors[] = array
		(
				'error_str' => $err_str,
				'query'     => $this->last_query
		);
	}

	/**********************************************************************
		*  Turn error handling on or off..
	*/

	function show_errors()
	{
		$this->show_errors = true;
	}

	function hide_errors()
	{
		$this->show_errors = false;
	}

	/**********************************************************************
		*  Kill cached query results
	*/

	function flush()
	{
		// Get rid of these
		$this->last_result = null;
		$this->col_info = null;
		$this->last_query = null;
		$this->from_disk_cache = false;
	}

	/**********************************************************************
		*  Get one variable from the DB - see docs for more detail
	*/

	function get_var($query=null,$x=0,$y=0)
	{

		// Log how the function was called
		$this->func_call = "\$db->get_var(\"$query\",$x,$y)";

		// If there is a query then perform it if not then use cached results..
		if ( $query )
		{
			$this->query($query);
		}

		// Extract var out of cached results based x,y vals
		if ( $this->last_result[$y] )
		{
			$values = array_values(get_object_vars($this->last_result[$y]));
		}

		// If there is a value return it else return null
		return (isset($values[$x]) && $values[$x]!=='')?$values[$x]:null;
	}

	/**********************************************************************
		*  Get one row from the DB - see docs for more detail
	*/

	function get_row($query=null,$output=OBJECT,$y=0)
	{

		// Log how the function was called
		$this->func_call = "\$db->get_row(\"$query\",$output,$y)";

		// If there is a query then perform it if not then use cached results..
		if ( $query )
		{
			$this->query($query);
		}

		// If the output is an object then return object using the row offset..
		if ( $output == OBJECT )
		{
			return $this->last_result[$y]?$this->last_result[$y]:null;
		}
		// If the output is an associative array then return row as such..
		elseif ( $output == ARRAY_A )
		{
			return $this->last_result[$y]?get_object_vars($this->last_result[$y]):null;
		}
		// If the output is an numerical array then return row as such..
		elseif ( $output == ARRAY_N )
		{
			return $this->last_result[$y]?array_values(get_object_vars($this->last_result[$y])):null;
		}
		// If invalid output type was specified..
		else
		{
			$this->print_error(" \$db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N");
		}

	}

	/**********************************************************************
		*  Function to get 1 column from the cached result set based in X index
	*  see docs for usage and info
	*/

	function get_col($query=null,$x=0)
	{

		$new_array = array();

		// If there is a query then perform it if not then use cached results..
		if ( $query )
		{
			$this->query($query);
		}

		// Extract the column values
		for ( $i=0; $i < count($this->last_result); $i++ )
		{
			$new_array[$i] = $this->get_var(null,$x,$i);
		}

		return $new_array;
	}


	/**********************************************************************
		*  Return the the query as a result set - see docs for more details
	*/

	function get_results($query=null, $output = OBJECT)
	{

		// Log how the function was called
		$this->func_call = "\$db->get_results(\"$query\", $output)";

		// If there is a query then perform it if not then use cached results..
		if ( $query )
		{
			$this->query($query);
		}

		// Send back array of objects. Each row is an object
		if ( $output == OBJECT )
		{
			return $this->last_result;
		}
		elseif ( $output == ARRAY_A || $output == ARRAY_N )
		{
			if ( $this->last_result )
			{
				$i=0;
				foreach( $this->last_result as $row )
				{

					$new_array[$i] = get_object_vars($row);

					if ( $output == ARRAY_N )
					{
						$new_array[$i] = array_values($new_array[$i]);
					}

					$i++;
				}

				return $new_array;
			}
			else
			{
				return null;
			}
		}
	}


	/**********************************************************************
		*  Function to get column meta data info pertaining to the last query
	* see docs for more info and usage
	*/

	function get_col_info($info_type="name",$col_offset=-1)
	{

		if ( $this->col_info )
		{
			if ( $col_offset == -1 )
			{
				$i=0;
				foreach($this->col_info as $col )
				{
					$new_array[$i] = $col->{$info_type};
					$i++;
				}
				return $new_array;
			}
			else
			{
				return $this->col_info[$col_offset]->{$info_type};
			}

		}

	}

	/**********************************************************************
		*  store_cache
	*/

	function store_cache($query,$is_insert)
	{

		// The would be cache file for this query
		$cache_file = $this->cache_dir.'/'.md5($query);

		// disk caching of queries
		if ( $this->use_disk_cache && ( $this->cache_queries && ! $is_insert ) || ( $this->cache_inserts && $is_insert ))
		{
			if ( ! is_dir($this->cache_dir) )
			{
				$this->register_error("Could not open cache dir: $this->cache_dir");
				$this->show_errors ? trigger_error("Could not open cache dir: $this->cache_dir",E_USER_WARNING) : null;
			}
			else
			{
				// Cache all result values
				$result_cache = array
				(
						'col_info' => $this->col_info,
						'last_result' => $this->last_result,
						'num_rows' => $this->num_rows,
						'return_value' => $this->num_rows,
				);
				error_log ( serialize($result_cache), 3, $cache_file);
			}
		}

	}

	/**********************************************************************
		*  get_cache
	*/

	function get_cache($query)
	{

		// The would be cache file for this query
		$cache_file = $this->cache_dir.'/'.md5($query);

		// Try to get previously cached version
		if ( $this->use_disk_cache && file_exists($cache_file) )
		{
			// Only use this cache file if less than 'cache_timeout' (hours)
			if ( (time() - filemtime($cache_file)) > ($this->cache_timeout*3600) )
			{
				unlink($cache_file);
			}
			else
			{
				$result_cache = unserialize(file_get_contents($cache_file));

				$this->col_info = $result_cache['col_info'];
				$this->last_result = $result_cache['last_result'];
				$this->num_rows = $result_cache['num_rows'];

				$this->from_disk_cache = true;

				// If debug ALL queries
				$this->trace || $this->debug_all ? $this->debug() : null ;

				return $result_cache['return_value'];
			}
		}

	}

	/**********************************************************************
		*  Dumps the contents of any input variable to screen in a nicely
	*  formatted and easy to understand way - any type: Object, Var or Array
	*/

	function vardump($mixed='')
	{

		// Start outup buffering
		ob_start();

		echo "<p><table><tr><td bgcolor=ffffff><blockquote><font color=000090>";
		echo "<pre><font face=arial>";

		if ( ! $this->vardump_called )
		{
			echo "<font color=800080><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Variable Dump..</b></font>\n\n";
		}

		$var_type = gettype ($mixed);
		print_r(($mixed?$mixed:"<font color=red>No Value / False</font>"));
		echo "\n\n<b>Type:</b> " . ucfirst($var_type) . "\n";
		echo "<b>Last Query</b> [$this->num_queries]<b>:</b> ".($this->last_query?$this->last_query:"NULL")."\n";
		echo "<b>Last Function Call:</b> " . ($this->func_call?$this->func_call:"None")."\n";
		echo "<b>Last Rows Returned:</b> ".count($this->last_result)."\n";
		echo "</font></pre></font></blockquote></td></tr></table>".$this->donation();
		echo "\n<hr size=1 noshade color=dddddd>";

		// Stop output buffering and capture debug HTML
		$html = ob_get_contents();
		ob_end_clean();

		// Only echo output if it is turned on
		if ( $this->debug_echo_is_on )
		{
			echo $html;
		}

		$this->vardump_called = true;

		return $html;

	}

	/**********************************************************************
		*  Alias for the above function
	*/

	function dumpvar($mixed)
	{
		$this->vardump($mixed);
	}

	/**********************************************************************
		*  Displays the last query string that was sent to the database & a
	* table listing results (if there were any).
	* (abstracted into a seperate file to save server overhead).
	*/

	function debug($print_to_screen=true)
	{

		// Start outup buffering
		ob_start();

		echo "<blockquote>";

		// Only show ezSQL credits once..
		if ( ! $this->debug_called )
		{
			echo "<font color=800080 face=arial size=2><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Debug..</b></font><p>\n";
		}

		if ( $this->last_error )
		{
			echo "<font face=arial size=2 color=000099><b>Last Error --</b> [<font color=000000><b>$this->last_error</b></font>]<p>";
		}

		if ( $this->from_disk_cache )
		{
			echo "<font face=arial size=2 color=000099><b>Results retrieved from disk cache</b></font><p>";
		}

		echo "<font face=arial size=2 color=000099><b>Query</b> [$this->num_queries] <b>--</b> ";
		echo "[<font color=000000><b>$this->last_query</b></font>]</font><p>";

		echo "<font face=arial size=2 color=000099><b>Query Result..</b></font>";
		echo "<blockquote>";

		if ( $this->col_info )
		{

			// =====================================================
			// Results top rows

			echo "<table cellpadding=5 cellspacing=1 bgcolor=555555>";
			echo "<tr bgcolor=eeeeee><td nowrap valign=bottom><font color=555599 face=arial size=2><b>(row)</b></font></td>";


			for ( $i=0; $i < count($this->col_info); $i++ )
			{
				echo "<td nowrap align=left valign=top><font size=1 color=555599 face=arial>{$this->col_info[$i]->type} {$this->col_info[$i]->max_length}</font><br><span style='font-family: arial; font-size: 10pt; font-weight: bold;'>{$this->col_info[$i]->name}</span></td>";
			}

			echo "</tr>";

			// ======================================================
			// print main results

			if ( $this->last_result )
			{

				$i=0;
				foreach ( $this->get_results(null,ARRAY_N) as $one_row )
				{
					$i++;
					echo "<tr bgcolor=ffffff><td bgcolor=eeeeee nowrap align=middle><font size=2 color=555599 face=arial>$i</font></td>";

					foreach ( $one_row as $item )
					{
						echo "<td nowrap><font face=arial size=2>$item</font></td>";
					}

					echo "</tr>";
				}

			} // if last result
			else
			{
				echo "<tr bgcolor=ffffff><td colspan=".(count($this->col_info)+1)."><font face=arial size=2>No Results</font></td></tr>";
			}

			echo "</table>";

		} // if col_info
		else
		{
			echo "<font face=arial size=2>No Results</font>";
		}

		echo "</blockquote></blockquote>".$this->donation()."<hr noshade color=dddddd size=1>";

		// Stop output buffering and capture debug HTML
		$html = ob_get_contents();
		ob_end_clean();

		// Only echo output if it is turned on
		if ( $this->debug_echo_is_on && $print_to_screen)
		{
			echo $html;
		}

		$this->debug_called = true;

		return $html;

	}

	/**********************************************************************
		*  Naughty little function to ask for some remuniration!
	*/

	function donation()
	{
		return "<font size=1 face=arial color=000000>If ezSQL has helped <a href=\"https://www.paypal.com/xclick/business=justin%40justinvincent.com&item_name=ezSQL&no_note=1&tax=0\" style=\"color: 0000CC;\">make a donation!?</a> &nbsp;&nbsp;<!--[ go on! you know you want to! ]--></font>";
	}

	/**********************************************************************
		*  Timer related functions
	*/

	function timer_get_cur()
	{
		list($usec, $sec) = explode(" ",microtime());
		return ((float)$usec + (float)$sec);
	}

	function timer_start($timer_name)
	{
		$this->timers[$timer_name] = $this->timer_get_cur();
	}

	function timer_elapsed($timer_name)
	{
		return round($this->timer_get_cur() - $this->timers[$timer_name],2);
	}

	function timer_update_global($timer_name)
	{
		if ( $this->do_profile )
		{
			$this->profile_times[] = array
			(
					'query' => $this->last_query,
					'time' => $this->timer_elapsed($timer_name)
			);
		}
			
		$this->total_query_time += $this->timer_elapsed($timer_name);
	}

}

?>